Wire-twisting apparatus

ABSTRACT

Wire-twisting apparatus adapted for twisting a plurality of individual strands of wire into a single cable comprising a twisting head mounted for rotary movement utilizing actuating means for providing twists in the wire at a given number per inch and of a predetermined tightness, the number of twists per inch being controlled by a lead screw and the number of twists per desired length being controlled by a counter.

United States Patent [1 1 Stei erwald Au 7 1973 1 WIRE-TWISTING APPARATUS 3,381,557 5 /1968 Dunn 82/5 3,616,531 11/1971 140/149 [75] Inventor: Conrad J. Stergerwald, Phoenix, 1,336,159 4/1920 140/149 1,382,258 6/1921 Turgeon 140/149 [73] Assignee: Honeywell Information Systems Inc.,

Waltham, Mass. Primary Examiner-Lowell A. Larson Filed Dec 2 1971 Attorney-James A. Pershon et a1.

N 4,253 [211 20 57 ABSTRACT [52] U S Cl 140/149 72/299 Wire-twisting apparatus adapted for twisting a plurality [51] Bzlf 7/00 ofindividual strands of wire into a single cable compris- [58] Fieid 15 ing a twisting head mounted for rotary movement uti- 17 b lizing actuating means for providing twists in the wire at a given number per inch and of a predetermined [56] References Cited tightness, the number of twists per inch being controlled by a lead screw and the number of twists per de- UNITED STATES PATENTS sired length being controlled by a counter. 3,222,908 12/1965 Molella... 72/299 3,368,433 2/1968 Roberts 82/23 10 Claims, 9 Drawing Figures WIRE-TWISTING APPARATUS BACKGROUND OF THE INVENTION This invention is directed to a wire twisting machine by which a plurality of individual strands of wire may be conveniently twisted together into a single cable suitable for use in the production wiring of complex electronic apparatus and devices. Although the machine was developed in connection with the production of cables having a plurality of insulated strands of wire, generally of contrasting colors, for use in electrical instruments, it is equally well adapted for producing cables for various other uses.

1. Field of the Invention This invention is directed to a relatively simple machine for twisting a plurality of strands of wire which can be operated by unskilled operators to produce high quality twisted cables wherein the number of twists per inch and the desired tightness of the twists are accurately controlled so that each twisted cable produced by the machine is identical to the other.

2. Description of the Prior Art Wire twisting apparatus have been provided heretofore which employed a pneumatically actuated eollet operatively connected to the shaft of an electric motor. The motor was controlled by a starting switch which was adapted to be manually actuated by an operator and a stop switch which was adapted to be actuated by suitable means such as a timer or a counter. Means were provided to actuate the stop switch after a predetermined number of turns of the collet. Although these prior art machines accomplished the automatic twisting of wire into a cable configuration, they failed to accurately control the number of twists per inch having a given tightness each and every time the machine operated so that cables were produced that could be used in sensitive electronic equipment which would transmit signals in the same manner without distortion.

SUMMARY OF THE INVENTION In accordance with the invention claimed, a new and improved wire twisting machine is provided which is simple to manufacture and service, may be operated by unskilled operators to produce high quality twisted cable uniform in the number of twists per given length, and having a tightness of the twist identical each and every twist, and is capable of being adjusted to handle wires of given lengths to provide predetermined numbers of twists per given unit of length of the wires to form identical cables suitable for use in the production of wiring of complex electronic apparatus intended to transmit signals of varying duration and magnitude.

Accordingly, it is an object of this invention to provide a relatively simple machine for twisting a plurality of strands of wire which can be operated by unskilled operators to produce high quality twisted cable with a minimum of manual effort on the part of the operator.

Another object of this invention is to provide an improved wire twisting machine which will twist a plurality of individual strands of wire of varying gauges, color combinations and lengths to produce cables of various predetermined lengths.

A further object of this invention is to provide an improved wire twisting machine which will handle various size wires and provide a predetermined number of twists per given length of wire, each having a predetermined tightness.

A further object of this invention is to provide an improved wire twisting machine which will produce a uniform ratio of turns or twists per unit length of wire to produce uniformly twisted cables.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is atop plan view of the wire twisting machine of this invention.

FIG. 2 is a front elevational view of the machine shown in FIG. 1.

FIG. 3 is an enlarged vertical sectional view of the machine shown in FIGS. 1 and 2, taken substantially on the line 33 of FIG. 2.

FIG. 4 is an enlarged vertical sectional view, taken on the line 4-4 of FIG. 2 showing one position of the associated elements of the machine.

FIG. 5 is a fragmentary vertical sectional view, similar to FIG. 4, showing another position of the associated elements of the machine.

FIG. 6 is an enlarged fragmentary plan view of a portion of the machine shown in FIG. 1 with some parts broken away and in horizontal section, taken on the line 66 of FIG. 2.

FIG. 7 is an enlarged side elevational view of one of the tension devices mounted on the machine as shown in FIGS. 1 and 2.

FIG. 8 is a vertical sectional view of the tension device shown in FIG. 7, taken on the line 8-8 of that Figure.

FIG. 9 is a schematic view or diagram illustrating the association of the various mechanical, electrical and pneumatic elements of the wire twisting machine of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the various views of the drawings for a more detailed description of the construction, operation and other features of the invention by characters of reference, FIGS. 1 and 2 illustrate the general features and placement of the wire twisting machine 10 on a suitable supporting and desk structure 11, which comprises a sturdy flat top 12, side enclosures l3 and 14 which define a central knee space 15 at the top of which several wire holding trays 16 extend outwardly for the convenient use of the machine operator. Secured to floor 17 within the knee space area 15 is a foot pedal 18 with its associated control box 19 (shown in FIG. 9) which is provided for operator control of machine 10.

Securely mounted to the flat top 12 of the support structure 1 l and parallel to and adjacent the front edge of the top is head stock 20, which contains a bearing supported rotatable spindle 21 (FIGS. 1, 2 and 6), the ends of which extend outwardly beyond the respective ends of the head stock to support and drive other rotatable elements hereinafter described.

Bearing blocks 23 and 24 are spacedly arranged directly below and in longitudinal alignment with a plane containing center-line 22 of the head stock spindle 21 (shown in FIG. 3) with bearing block 23 being positioned adjacent the right end of head stock 20 and secured to flat top 12 of supporting structure 11 by screws 25. Bearing block 24 is secured to flat top 12 in accurate longitudinal and vertical alignment with bearing block 23, but spaced apart from bearing block 23 a predetermined distance to support the reduced end portions 26 and 27 of the Acme type threaded screw 28 journaled therein. The desired length, diameter and number of threads per inch of threaded screw 28 is predicated on several factors which will be explained in more detail as this description proceeds.

A pair of guide rails in the form of round, smooth surfaced shafts 29 and 30 are rigidly secured at their ends in suitable mounting blocks 31 and 32, which blocks are fastened to table top 12 by means of screws 33. Shafts 29 and 30 are mounted in blocks 31 and 32 about the same height above the flat top 12 as: threaded screw 28 and extend in parallel relation thereto, one on each side thereof a slight distance beyond bearing block 24. As so positioned, the shafts are adapted to serve as guide rails for a sliding tail stock or guide base 34 mounted to slidingly move outwardly from its starting position to full extent of required travel which is only limited by the length of threaded screw 28.

The tail stock or guide base 34 is mounted in sliding relation on shafts 29 and 30 by means ofa plurality of depending pillow blocks 35 which are provided with aligned bores 36 through which the shafts 29 and 30 ex tend. These pillow blocks are secured to the under side of the guide base by any suitable removable means and are of sufficient height to support the guide base 34 slightly above the guide rail shafts and the threaded screw 28 to allow for free sliding movement of the guide base on these shafts.

The guide base 34 is provided on its underside with an integral depending portion 37 which is located midway of the base and extends transversely across the base from one side to the other. Portion 37 (as shown in H6. 3) is provided with a central bore 38 having a counter bore 39 at its outer end and extends into a cutout or longitudinal slot 40 in portion 37 at its inner end.

The base 38, counter bore 39 and the slot 40* provide a suitable locating and holding means for a manually releasable spring biased plunger rod 41, spring 42 and an actuating nob 43 which is attached to the plunger rod 41 at its outer end. Slot 40 provides ample space for the movement of a screw pin holder 44 which is removeably secured to the protruding inner end of the plunger rod 41 by means of a set screw 45.-

The screw pin holder 44 has an integral depending narrow portion 46 which extends downwardly a sufficient distance below the horizontal center-line 47 of the threaded screw 28 to allow for the exact positioning of the axis of a screw thread contacting pin 48 on the horizontal center-line 47 of screw 28. Pin 48 is removably secured in the depending portion 46 of the screw pin holder 44 by means of a set screw and guided into or out of contact with the threads of screw 28 by a suitable guide member 49 which is secured to the underside of the depending portion 37 of the guide base 34.

The screw thread contact pin 48 is provided at its outer end or tip 50 with a conical or other suitably shaped end portion which mates with the angular sides of the threads of screw 28 to provide the necessary cam action to advance the tail stock or guide base 34 away from the head stock 20 with uniform speed when screw 28 is rotated.

In order to provide controlled motive power for operation of the several rotatable components of the wire twisting machine 10, including the Acme type threaded screw 28, a wire clamping and holding chuck or device 51, spindle 21, brake mechanism 52 moving parts (not shown), spur-gear 53 and pulsating device 54, a variable speed D.C. electric motor 55 is mounted on table top 12 directly behind the head stock 20 by means of bolts 56.

The variable speed electric motor 55 receives its direct current electrical energy through a lead 57 which is connected to a power supply transformer and brake control box 58 housing an A.C. to D. C. transforming facility for actuating brake mechanism 52. The control box 58 receives its alternating current through a lead 59 connected to a l 10-volt source by means of receptacle 60, best illustrated in the schematic diagram of FIG. 9. FIG. 9 also shows the relative association of other electrically operated elements of the machine such as pulsating device 54, counter mechanism 61, solenoid valve 62, and the micro-switch 63, the functions of which will be further explained.

The variable speed motor 55 is adapted to drive or rotate spindle 21, spur gear 53 fixedly attached to the projecting left end of spindle 21, pulsating device 54 which is rigidly mounted on an angle bracket 64 secured to table top 12, wire clamping and holding device 51 which is fixed to the projecting right end of spindle 21 and the Acme type threaded screw 28 through three separate non-slip drive trains. Each of the drive trains utilizes belts and pulleys of the gear toothed variety to provide a positive non-slip, smooth drive for all the elements driven. This results in accurate control and count of the number of revolutions required for twisting wire in a predetermined manner.

The main drive train consists of a drive pulley 65 attached to an extension shaft of motor 55, a driven pulley 66 attached to the left end of spindle 21, and a suitable non-slip belt 67. The drive train for the pulsating device consists of a pulley 68 which is attached to a projecting end of the pulsating devices shaft, a pulley 69 which is attached to the left end of spindle 21 and a non-slip belt 70.

The third drive train which is utilized to rotate the wire clamping and holding device 51 and to rotate screw 28 consists of two similar sized pulleys 71 and 72, and a smaller idler pulley 73 which is rotatively attached to a bracket 74 midway between pulleys 71 and 72 (as shown in FIG. 3). Bracket 74 is secured to table top 12 in any suitable manner. Pulleys 72 and 73 are driven by non-slip belt 75.

The upper pulley 71 is attached in driving relation by a ,Woodruff type key 76 to a sleeve member 77. The central bore of sleeve member 77 is adapted to receive the projecting end of spindle 21 to which it is attached in driving relation therewith by pin 78. This connection causes sleeve member 77 and pulley 71 to be rotated as a single unit by spindle 21. Pulley 72 is attached in driving relation to the reduced end portion 26 of the Acme type threaded screw 28.

Sleeve member 77 extends outwardly beyond pulley 71 a sufficient distance to allow its central bore to receive an inwardly extending shaft portion 79 which is preferably an integral part of jaw 80 of the plier-like wire clamping and holding device 51. Shaft portion 79 is attaclgegl in rotative fixed relation with sleeve 77 by means ofa drive pin 81. The otherjaw 82 of the clamping device 51 is formed to have the same cross section as jaw 80, and together with jaw 82 provides a flat surface on both sides of the assembled device of sufficient thickness, especially at their interlocking point of contact 83, to receive, clamp, and hold at least a pair of wires to be twisted. It should be noted that the wire receiving space between the jaws and 82 at their interlocking point of contact 83 is directly on the vertical center line 22 of the spindle 21 and the interconnected extending shaft portion 79 of the clamping and holding device 51 as shown in FIG. 3.

Jaw 82 is provided with a bifurcated boss portion 84 which is adapted to receive a central extension or tab 85 which is integral with jaw 80, and through which the two jaws are pivoted as at 86 so as to operate in a similar manner as a conventional plier, as clearly illustrated in FIG. 6. The jaws 80 and 82 are normally held in closed clamping relation by the spring pressure exerted on the inner surface of jaw 82 by a commonly used Vlier pin 87, one part of which is threaded into jaw 80.

The interlocking pivoted jaws 80 and 82 of the wire clamping and holding device 51 may be opened at their point of contact 83, to remove completed twisted wire assemblies or to insert pairs of wires to be twisted therebetween, by foot pressure being applied to the foot pedal 18 by the machine operator. Foot pressure on pedal 18 causes the pedal to be moved from normal up position A to the down position B (as shown in dotted line in FIG. 9) thus causing the clamping device 51 to be rotated to the correct accessable loading or unloading positions, each loading and unloading operation. The flat sides of the jaws assume a substantially horizontal position, as shown in FIGS. 3 and 6, at the time of each loading and unloading operation. Depressing of the foot pedal 18 causes compressed air under regulated pressure to move from the control box 19 through the pipes or air lines 90 and 91, open solenoid valve 62 and air line 92 to exert pressure on piston 93 and piston rod 94 of a one-way pneumatic drive means 95. The pneumatic drive means 95 is rigidly secured to the rear side of head stock 20 by a suitable angle bracket 96. This drive means causes the yoke member 97 and its lateral extensions 98 and 99 which are pivoted at a point 100 to a fixed bracket 101 to be moved radially outward at its pivoted point of attachment 102 with the end of piston rod 94 to effect the opening of the clamp jaws.

The yoke member 97 is formed with an annular ring portion 103 having a circular opening 104, the center of which is aligned with the center of spindle 21 and the shaft portion 79 of the jaw 80, and which is of large enough diameter to surround the outer perimeter surface of an outer slidable sleeve member 105. Sleeve member 105 is supported in sliding relation on the outer perimeter surface of the rotatable inner sleeve member 77, previously mentioned and shown in FIG. 6. The central bore of the sleeve member 105 is provided at its outer end with a wide surfaced chamfered counterbore 106 which is adapted to engage the round surface end portion 107 of the clamp jaw 82 in camlike relation to force the clamp jaw inwardly about its pivot 86, overcoming the resistance of the Vlier pin 87, and thereby opening the jaws of the wire clamping and holding device 51 at their point of contact 83, as indicated by the angle of movement 83a.

The opening of the clamp jaws above described is accomplished by the forced longitudinal sliding movement of slidable sleeve member 105, which receives its movement through its connection with the annular ring portion 103 of yoke member 97 which surrounds it with ample clearance to move radially outwardly therefrom as indicated by the angle of movement 108 in FIG. 6.

To this end, the sleeve member 105 is provided with an annular groove 105a which is adapted to receive the stub inner ends of a pair of suitable set screws 109. These set screws are removably secured in threaded holes centrally located at the top and bottom of the annular ring portion 103 of the yoke member 97. Their stub ends project into the annular groove 105a in the slidable sleeve 105 to provide a connection between yoke member 97 and sleeve member 105, causing sleeve 105 to move longitudinally in either direction to open or close the jaws of the wire clamping and holding device 51.

Referring particularly to FIGS. 1, 2 and 6 of the drawings it should be observed that the individual color coated wires 110 which are to be twisted to form the twisted wire assemblies 111 of the desired length, are first loaded or placed between the open jaws of the clamping and holding device 51 and are secured therein by the closing of the jaws. The previously stripped ends of these wires extend outwardly from their clamped position 83 in the jaws. The outer ends of each wire extend adjacent to and then pass beyond a wire separating guide pin 112 which is vertically mounted on the center line 113 of the spindle 21, guide base 34 and screw 38'to keep the wires being twisted in aligned relationship therewith.

The guide pin 112 is rigidly mounted in a specially shaped block member 114 which is securely attached to and positioned centrally and to one end of the movable guide base 34 so as to travel as an integral part thereof. The block member 114 is provided with an upstanding rear portion having vertical surfaces 115 which meet at their apex on the center line 1 13 of spindle 21 to provide surfaces upon which an identical pair of tension devices 116 are non-rotatively mounted.

The tension devices 116 are similar in most respects to the commonly used thread tension devices used on sewing machines, except for the provision of U-shaped 1 wire loops 117 rigidly mounted on block member 114 to project upwardly between the inner faces of the adjustable discs 118 of the tension devices, as clearly illustrated in FIGS. 7 and 8. These wire loops 117 are fabricated of the same gage or diameter material as the individual wires to be twisted, to keep the inner opposed faces of the discs 118 parallel to each other and thus to limit and control the amount of tension which may be applied to the wires 110 that are held in yielding relation therein. The wires 110 extend beyond the tension devices where they are yieldingly threaded through suitable wire supporting clips 119 which are secured to the rear surface of block member 114, as shown in FIG. 6.

As illustrated in FIGS. 4, 5 and 9, the spur gear 53 has a flat toothless portion 120 where several of the gear teeth have been removed. Spur gear 53 is normally in contact with the front toothed edge 121 of a vertical, reciprocally actuated gear rack 122. Rack 122 is normally urged into contact with the flat toothless portion 120 or into meshing engagement with the gear teeth 123 of spur gear 53 by a spring actuated plunger 124 which presses against the rear edge of the gear rack 122 and is adapted to control the rotation of spur gear 53, spindle 21 and its associated elements including the wire clamping device 51.

To accomplish the desired positioning of wire clamping device 51 and to hold it in this position whenever device 51 is opened for removal of twisted wire assemblies or open for the insertion of wires to be twisted, spur gear 53 is secured to spindle 21 by means of a set screw 124a in a pre-determined radial position relative to its flat portion 120 and the horizontal axis 125 of clamping device 51. This arrangement causes the flat side surfaces of the jaws of device 51 to be positioned substantially parallel to table top 12, or tipped slightly forward therefrom, whenever the front toothed edge 121 of rack 122 is brought into contact with the flat portion 120 of spur gear 53, after the rotation of gear 53 has been stopped, thereby placing the clamping device 51 in the position described for removal and load ing of the wires.

The gear rack 122 and its associated activating components such as air cylinders 126 and 127 are preferably installed in the side enclosure 13 under table top 12 with all of these components supported by a structural frame member 128. Frame member 128 comprises downwardly extending side members 129 and 130 and a joining cross member 131 with the assembled frame being rigidly secured to the underside of table top 12 in any suitable manner such as by welding. The air cylinder 126 is hung and supported in the frame cross member 131 by means of a clamp nut 132 threaded to its upper end, allowing its piston rod 133 to extend upwardly therefrom. Piston rod 133 has an integral clevis member 134 at its end, which is pivotally attached at 135 to a male clevis member 136 which is notched to receive and support the lower end of gear rack 122 by means of screws 137.

The gear rack 122 is long enough to extend upwardly through a rectangular opening 138 in table top 12, to a position adjacent to and in parallel alignment with gear teeth 123 of spur gear 53 as shown in FIG. 4, and is guided during its upward and downward reciprocating movements by suitable guide plates 139 which are installed in the structural frame 128, adjacent the sides of the rack gear. Gear rack 122 is also guided during its vertical movement by a hinge member 140 which is attached at 1400 in pivotal relation to the side member 129 of frame member 128 by plates 141. Plates 141 enclose the sides of the hinge and are attached to the lower edges of the side member by screws 142.

Hinge member 140 and its milled out rabbet 143 extending the full length thereof receives and guides the toothed face and edge of rack 122 during its vertical movement; Hinge member 140 extends vertically upwardly through opening 138 in table top 12 to substantially the top end of rack 122 when both are in their lowermost positions at rest against the inside face 144 of the frame side member 129 (as shown in FIG. 4). Rack 122 is held in this position by the pressure exerted on its outside edge by spring actuated plunger 124 which is rigidly mounted above table top 12 as shown.

From this described position, rack 122 can be raised approximately inches or a sufficient distance to effect a complete revolution of spur gear 53 in order to position the flat portion 120 of the spur gear against rack 122 to cause opening of the jaws of the wire clamping device 51, as previously described, at the end of a wire twisting cycle.

In order to position spur gear 53 in driving arrangement with motor 55 and belt 67 to effect another wire twisting operation, rack 122 must be moved out of contact with the gear teeth 123 or the flat portion of spur gear 53. This may be accomplished by the activation of the small (one-way) air cylinder 127, which is secured to the outer face of side member 129 of frame 128. Air cylinder 127 is provided with the usual spring biased piston 146 which is adapted to project through an aperture in the side member 129 of frame 128 to contact the front edge 148 of binge member 140, to cause the hinge member to be moved radially outwardly about its pivot point 140a away from the inside face 144 of side member 129 and at the same time causing the gear rack 122 with which it is always in contact in the rabbet 143 to move radially outwardly about its pivotal point of attachment 135 with clevis member 134. This action causes the rack to move radially out of contact with spur gear 53, overcoming the force of the spring actuated plunger 124, while the rack is being lowered to allow free rotation of spur gear 53 and its associated parts to position them for another wire twisting operation.

In order to control the opening and closing of the jaws of the wire clamping and holding device 51 at the end of a wire twisting cycle to remove the assemblies so formed or to insert new wires to be twisted, all of the rotative elements have been braked to stop by the sequential action of the pulsating device 54, counter 61 and the solenoid valve 62 which controls the passage of compressed air to the air operated cylinder 95. This control is accomplished by the activation of the microswitch 63 which is mounted on a structural part of the machine above the table top 12 with its switch lever 63a aligned with one side of the reciprocable gear rack 122, as shown in FIGS. 4 and 5.

A suitable angular shaped lug 149 is secured to the side of the gear rack 122 and is adapted to engage the switch lever 63a when the rack is moved upward to its maximum position to close the circuit'through the electrical leads 150 and 151, thereby activating the solenoid of valve 62 to open said valve and causing the air cylinder 95 to be activated to perform its function as previously described. Wire clamping device 51 and solenoid valve 62 are automatically closed when the circuit from the valve 62 to the micro-switch 63 is opened by engagement of lug 149 with switch lever 63a when the gear rack 122 is moved down to its lowermost position. Air is exhausted from cylinder 95 through air line 92 and the exhaust-valve 92a as seen in FIG. 9. Since air exhaust means connected to pneumatic systems including single and double acting pistons are well known in the art, only a symbolic exhaust valve such as valve 92a, among others, will be shown for clarity purposes.

It should be understood that other electrical circuits and air line systems not described in the preceding paragraphs are utilized in the functioning of this wire twisting machine, and they will be described in the following paragraphs pertaining to the operation of the machine.

OPERATION .The wire twisting machine of this invention is designed to automatically perform its functions, with few simple manual manipulations by an unskilled operator seated comfortably in front on the machine with his hands and feet conveniently accessible to the loading, unloading and control mechanism of the machine.

The operator starts the wire twisting operation by pushing in the plunger release knob 43, which releases the contact pin 48 from the Acme type thread of screw 28. While holding the knob in with one hand, he then manually slides the tail stock guide base 34 over the screw 28 on the guide rails 29 and 30 to the position for starting the twisting operation, as shown in FIGS. 1 and 2 of the drawings. He then releases plunger knob 43, allowing the contact pin 48 to enter the helical space between the threads of the screw, freeing both hands for the next wire loading function with the guide base properly positioned.

The operator next places his foot on the floor mounted pedal 18 and moves the pedal down from its position A to position B and momentarily holds it there, opening a valve in the foot pedal control box 19, causing compressed air from a suitable source (not shown) to pass through feed line 190, open valve 19b, and into lines 90, 90a and 91. Air line 91 is blocked by the closed solenoid valve 62. Air line 90a is connected to the lower end of the dual acting air cylinder 126, forcing its piston 126a and piston rod 133 up from its lowest position A to its uppermost position B, forcing clevis 134, the pivotally connected clevis member 136 and the gear rack 122 upwardly as indicated by dotted line in FIG. 9. Air trapped above piston 126a is exhausted through air lines 152, 153 and a one-way ex haust valve 153a to atmosphere.

As the gear rack 122 is being raised by the action of piston 126a in air cylinder 126, the teeth on rack 122 have been caused to mesh in a non-clashing fashion with teeth 123 of spur gear 53 due to the yielding effect of the spring actuated plunger 124 on the edge of the rack, thus causing spur gear 53 to rotate until the teeth of the rack are in contact with the flat portion 120 of the spur gear. At this point in rotation of spur gear 53, the wire clamping device 51 is in the desired accessible position for loading wires in the machine, as previously described.

During the upward movement of rack 122 to position the wire clampingdevice 51 for receiving wires, lug 149 on the side of the rack actuates the micro-switch lever 63a to complete an electric circuit, through leads 150 and 151 to solenoid valve 62, thereby opening the valve and causing pressurized air in air line 91 to pass through the valve into air line 92. Air line 92 transmits the air under pressure to the rear of piston 93 in cylinder 95, causing the piston shaft 94 to be forced forwardly, moving the attached end of yoke member 97 radially outward about its pivot point 100. This action results in the forced outward movement of the slidable sleeve member 105 to open the jaws of the clamping device 51.

With the operator still holding the foot pedal 18 in down position B, thereby maintaining the open position of the jaws of the wire clamping device 51 with the teeth of gear rack 122 adjacent the flat portion 120 of spur gear 53, he then takes a pair of insulated stripped ended wires from tray 16 or any other convenient source of supply, and places the stripped end of two wires in vertical parallel relationship between the jaws of the clamping device, allowing the insulated portions and other stripped ends of the wires to extend out from the clamp jaws.

Holding the wires in this position he then removes his foot from the pedal 18 allowing the pedal to return up to its normal position A, thereby activating valve 19b in the foot pedal control box 19, to close the port connected with air-line 90, and opening the port connected with air-line 153. This action causes the pressurized air in lines 90, 91 and 92 to be released to atmosphere through the exhaust port 92a and the spring in cylinder 95 to retract piston 93, piston rod 94, yoke 97 and sleeve to their left most positions shown in the drawings, thereby relieving pressure on the rounded end of clamp jaw 82. This action causes the Vlier pin 87 to exert pressure on the inside surface of jaw 82 to close the jaw tightly against the wires and the surface of its mating stationary jaw 80, slightly bending the wires at the interlocking contact point 83, to securely hold both wires in clamping device 51.

Having thus secured the stripped ends of both wires in the clamping device, the operator then threads each wire past the guide pin 112, through and between the parallel inner sides of discs 118 of the adjustable tension device 116, and into and through the wire supporting clips 119. As shown in FIGS. 1 and 2, the pair of wires and the other associated components of machine 10 are now in position for the twisting operation to begin.

The foot pedal 18 having been previously returned to its normal up position A, thereby opening the port in valve 19b, causes pressurized air to flow through airline 153, its extension 153a, and air-line 152 to actuate piston 146 of cylinder 127 and piston 126a of cylinder 126. This action causes downward movement of rack 122.

The activation of cylinder 127 causes its piston 146 and piston rod 147 to be forced forwardly, overcoming the resistance of a return spring in the cylinder and causing the piston rod 147 to exert sufficient pressure against the edge of the pivoted hinge member 140 which bears against the toothed edge of the gear rack 122 to move the gear rack and hinge member radially outwardly from their respective points 140a and 135. This action causes separation of the toothed edge of the gear rack from the flat portion on the spur gear 53 with ample clearance therebetween and allows the gear rack 122 to be returned to its normal down position as shown in FIG. 4. This is accomplished by the pressurized air in the lines 153 and 152 entering the cylinder 126 at its upper endand exerting pressure on the top of piston 126a causing the piston, its piston rod 133 and the connected gear rack 122 to be forced down-.

wardly to its normal at rest lower position. The spent air in the cylinder 126 is evacuated through air-line 90a and exhaust valve 90b (symbolically shown) to atmosphere in a suitable manner.

All of the respective machine elements and wires have now been placed in their proper relation to begin the wire twisting operation which is accomplished in the following manner.

The DC. variable speed motor 55 is energized by direct current from the power supply control box 58 through the lead wire 57, either automatically or by the flip of a switch (not shown) convenient to the operator, causing its pulley 65 to revolve and transferring this rotary movement to all the other machine components requiring rotational movement through the various pulleys and belts which form the several drive trains previously described with the proper ratio and speed re quired of each component.

The wire clamping and holding device 51, the Acme type threaded screw 28 and the shaft of the pulsating device 54 are therefore caused to revolve in unison, but

if desired, at different speeds to accomplish their particular function. The revolving of the clamping and holding device 51 causes the separate wires to be twisted around each other, and each complete revolution of the device and the resultant twist of the wires automatically results in a signal being received by the pulsating device 54, which automatically transfers the count of each complete revolution to the counter mechanism 61 and to the power supply and control box 58 by means of a suitable electrical circuit 154. The counter mechanism is adapted to count and record each and every revolution of the clamping and holding device 51 and to stop the revolution of the associated components when a specific number of wire twists have been completed.

It should be understood that as the wires are being twisted the tail stock or guide base 34 must be moved away from its starting position an exact distance which is determined by the tightness and length desired of each twist. The specific distance of outward movement of the guide base 34 is accomplished by the predetermined helix angle anddiameter of the threads of screw 28. As it is rotated, it moves the guide base 34 outwardly a specific distance by means of contact pin 48 which projects between the threads, causing each revolution of the screw 28 to move the wire holding guide base 34. This movement continues until the desired number of twists have been completed.

When the desired number of twists have been completed and recorded by the counter mechanism 61, the counter sends a signal to the power supply box 58 which deenergizes motor 55. At this time the clamping device 51 may be opened and the twisted wire assembly 111 removed from the machine, as heretofore explained.

Although but one embodiment of the invention has been shown and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention .or fromthe scope of the appended claims.

I claim:

1. A wire twisting machine adapted for twisting a plurality of individual strands of wire into a single cable comprising, in combination:

a base,

a head stock secured to said base in fixed position,

an elongated track secured to said base and extend ing outwardly from said head stock,

a tail stock slidably mounted on said track for move ment towards and away from said head stock,

screw means by which said tail stock is moved along said track extending outwardly from said head stock in the same direction as said track, said screw means providing a predetermined number of twists per unit length of the wires,

a spindle rotatably mounted in said head stock,

a pair of jaws rigidly wired to said spindle for rotation therewith and pivotally mounted for cooperatively engaging to detachably hold one end of each of a pair of strands of wire,

means for rotatably positioning said jaws in a predetermined angular position with respect to said base for ease in placing wires in said jaws,

said latter means comprising a spur gear mounted on said spindle,

said spur gear having a toothless portion around a part of its periphery,

a rack for selectively engaging said spur gear for rotating said spindle independently of said screw means for rotating said jaws to a predetermined loading position prior to a wire twisting operation,

restraining means attached to said tail stock, one for supporting each of said wires in angularly spaced relationship with respect to each other, said restraining means causing said wires to be pulled outwardly therefrom to compensate for the foreshortenin g of said wires as they are twisted by said chuck and the movement of said tail stock along said track,

said tail stock being detachably connected to said screw means for actuation along said track upon rotation of said screw means,

means for rotating said spindle and said screw means for twisting said wires as said tail stock is moved along said track by said screw means, and

indexing means connected to said spindle to control said rotating means to cause said spindle to rotate a requisite number of revolutions to twist said wires into a cable of a predetermined number of twists per unit of length thereof.

2. The wire twisting machine set forth in claim 1 in further combination with means by which said tail stock may be selectively threadedly connected to said screw means for moving along said screw means upon rotation thereof.

3. The wire twisting machine set forth in claim 1 in further combination with:

a pulsating device connected to said spindle for sensing the amount of rotation thereof and generating electrical pulses in response thereto,

a counter connected to and actuated by the pulses generated by said pulsating device,

said counter upon reaching a predetermined count deenergizing said rotating means to stop the rotating of said spindle and the twisting of said wires.

4. A wire twisting machine adapted for twisting a plurality of invididual strands of wire into a single cable comprising:

a base,

a head stock secured to said base in fixed position,

an elongated track secured to said base and extending outwardly from said head stock,

a tail stock slidably mounted on said track for movement towards and away from said head stock,

screw means by which said tail stock is moved along said track extending outwardly from said head stock in the same direction as said track,

a spindle rotatably mounted in said head stock,

a chuck means rigidly secured to said spindle for rotation therewith and adapted to have one end of eachof a pair of strands of wire to be twisted removably secured thereto,

said chuck means comprising a pair of jaws pivotally mounted for cooperatively engaging to detachably hold said strands of wire,

frictional type retaining means attached to said tail stock for supporting said wires in angularly spaced relation with respect to each other, said retaining means causing the wires to be pulled slidingly outwardly therefrom to compensate for the foreshortening of said wires as they are twisted by said chuck and the movement of said tail stock along said track,

said tail stock being detachably connected to said screw means for actuation along said track upon rotation of said screw means,

means for rotating said spindle and said screw means for twisting said wires as said tail stock is moved along said track by said screw means, and

means for rotatably positioning said jaws in a predetermined angular position with respect to said base for ease in placing in and removing wires from said jaws,

said latter means comprising a spur gear mounted on said spindle,

said spur gear having a toothless portion around a part of its periphery,

a rack for selectively engaging said spur gear for rotating said spindle independently of said screw means for rotating said jaws to a predetermined loading position prior to a wire twisting operation, and

interlocking means for positioning said rack in tooth engagement with said spur gear in timed sequence with the wire twisting rotation of said spindle.

5. The wire twisting machine set forth in claim 4 in further combination with:

a pneumatic means for actuating said rack, and

an operator control for actuating said first pneumatic means in time sequence with the wire twisting rotation of said spindle.

6. The wire twisting machine set forth in claim 5 wherein:

said jaws are biased into engagement with each other to clamp one end of said strands of wire therebetween,

a sleeve movably mounted on said spindle for engaging said jaws to bias them in jaw opening direction, and

a second pneumatic means for actuating said sleeve,

said operator control actuating said first and second pneumatic means in time sequence with the wire twisting rotation of said spindle.

7. The wire twisting machine set forth in claim 6 in further combination with means by which said tail stock may be selectively threadedly connected to said screw means for moving along said screw means upon rotation thereof.

8. The wire twisting machine set forth in claim 7 in further combination with an indexing means connected to said spindle by means of which said rotating means is controlled to cause said spindle to rotate the requisite number of revolutions to twist said wires into a cable of a predetermined number of twists per unit of length thereof.

9. The wire twisting machine set forth in claim 8 wherein said screw means is provided with an Acme thread for providing a predetermined number of twists per unit of length of the wire.

10. The wire twisting machine set forth in claim 4 i further combination with:

a pulsating device connected to said spindle for sensing the amount of rotation thereof and generating electrical pulses in response thereto,

a counter connected to and actuated by the pulses generated by said pulsating device,

said counter upon reaching a predetermined count deenergizing said rotating means to stop the rotating of said spindle and the twisting of said wires. 

1. A wire twisting machine adapted for twisting a plurality of individual strands of wire into a single cable comprising, in combination: a base, a head stock secured to said base in fixed position, an elongated track secured to said base and extending outwardly from said head stock, a tail stock slidably mounted on said track for movement towards and away from said head stock, screw means by which said tail stock is moved along said track extending outwardly from said head stock in the same direction as said track, said screw means providing a predetermined number of twists per unit length of the wires, a spindle rotatably mounted in said head stock, a pair of jaws rigidly wired to said spindle for rotation therewith and pivotally mounted for cooperatively engaging to detachably hold one end of each of a pair of strands of wire, means for rotatably positioning said jaws in a predetermined angular position with respect to said base for ease in placing wires in said jaws, said latter means comprising a spur gear mounted on said spindle, said spur gear having a toothless portion around a part of its periphery, a rack for selectively engaging said spur gear for rotating said spindle independently of said screw means for rotating said jaws to a predetermined loading position prior to a wire twisting operation, restraining means attached to said tail stock, one for supporting each of said wires in angularly spaced relationship with respect to each other, said restraining means causing said wires to be pulled outwardly therefrom to compensate for the foreshortening of said wires as they are twisted by said chuck and the movement of said tail stock along said track, said tail stock being detachably connected to said screw means for actuation along said track upon rotation of said screw means, means for rotating said spindle and said screw means for twisting said wires as said tail stock is moved along said track by said screw means, and indexing means connected to said spindle to control said rotating means to cause said spindle to rotate a requisite number of revolutions to twist said wires into a cable of a predetermined number of twists per unit of length thereof.
 2. The wire twisting machine set forth in claim 1 in further combination with means by which said tail stock may be selectively threadedly connected to said screw means for moving along said screw means upon rotation thereof.
 3. The wire twisting machine set forth in claim 1 in further combination with: a pulsating device connected to said spindle for sensing the amount of rotation thereof and generating electrical pulses in response thereto, a counter connected to and actuated by the pulses generatEd by said pulsating device, said counter upon reaching a predetermined count deenergizing said rotating means to stop the rotating of said spindle and the twisting of said wires.
 4. A wire twisting machine adapted for twisting a plurality of invididual strands of wire into a single cable comprising: a base, a head stock secured to said base in fixed position, an elongated track secured to said base and extending outwardly from said head stock, a tail stock slidably mounted on said track for movement towards and away from said head stock, screw means by which said tail stock is moved along said track extending outwardly from said head stock in the same direction as said track, a spindle rotatably mounted in said head stock, a chuck means rigidly secured to said spindle for rotation therewith and adapted to have one end of each of a pair of strands of wire to be twisted removably secured thereto, said chuck means comprising a pair of jaws pivotally mounted for cooperatively engaging to detachably hold said strands of wire, frictional type retaining means attached to said tail stock for supporting said wires in angularly spaced relation with respect to each other, said retaining means causing the wires to be pulled slidingly outwardly therefrom to compensate for the foreshortening of said wires as they are twisted by said chuck and the movement of said tail stock along said track, said tail stock being detachably connected to said screw means for actuation along said track upon rotation of said screw means, means for rotating said spindle and said screw means for twisting said wires as said tail stock is moved along said track by said screw means, and means for rotatably positioning said jaws in a predetermined angular position with respect to said base for ease in placing in and removing wires from said jaws, said latter means comprising a spur gear mounted on said spindle, said spur gear having a toothless portion around a part of its periphery, a rack for selectively engaging said spur gear for rotating said spindle independently of said screw means for rotating said jaws to a predetermined loading position prior to a wire twisting operation, and interlocking means for positioning said rack in tooth engagement with said spur gear in timed sequence with the wire twisting rotation of said spindle.
 5. The wire twisting machine set forth in claim 4 in further combination with: a pneumatic means for actuating said rack, and an operator control for actuating said first pneumatic means in time sequence with the wire twisting rotation of said spindle.
 6. The wire twisting machine set forth in claim 5 wherein: said jaws are biased into engagement with each other to clamp one end of said strands of wire therebetween, a sleeve movably mounted on said spindle for engaging said jaws to bias them in jaw opening direction, and a second pneumatic means for actuating said sleeve, said operator control actuating said first and second pneumatic means in time sequence with the wire twisting rotation of said spindle.
 7. The wire twisting machine set forth in claim 6 in further combination with means by which said tail stock may be selectively threadedly connected to said screw means for moving along said screw means upon rotation thereof.
 8. The wire twisting machine set forth in claim 7 in further combination with an indexing means connected to said spindle by means of which said rotating means is controlled to cause said spindle to rotate the requisite number of revolutions to twist said wires into a cable of a predetermined number of twists per unit of length thereof.
 9. The wire twisting machine set forth in claim 8 wherein said screw means is provided with an Acme thread for providing a predetermined number of twists per unit of length of the wire.
 10. The wire twisting machine set forth in claim 4 in further combination with: a pulsating device conNected to said spindle for sensing the amount of rotation thereof and generating electrical pulses in response thereto, a counter connected to and actuated by the pulses generated by said pulsating device, said counter upon reaching a predetermined count deenergizing said rotating means to stop the rotating of said spindle and the twisting of said wires. 